Front and lateral loading mechanism

ABSTRACT

A front and lateral loading mechanism, primarily for lift trucks, in which a load supporting structure is mounted on the forward end of a boom and the boom is connected to a carriage by a pantograph mechanism capable of operating in an overcenter relationship to extend laterally to either side. One of the two links of the pantograph mechanism is continuous and the other link has upper and lower arms rigidly connected to one another by a shaft journalled in the continuous link, with the arms on the opposite sides thereof. One link is pivotally connected to the carriage and slidably connected to the boom, and the other link is slidably connected to the carriage and pivotally connected to the boom. The carriage is normally mounted on an upright of a lift truck for raising and lowering a load, and the load supporting structure, which may be a fork section, is capable of slewing from one side to the other as the pantograph mechanism moves the boom laterally.

United States Patent Hansen et al.

Oct. 2, 1973 FRONT AND LATERAL LOADING Primary Examiner-Gerald M. Forlenza MECHANISM Assistant Examiner -Lawrence J. Oresky [75] Inventors: Howard C.llansen;.lohn S.Messner, i g ig g g Hobbs Maunce Green both of Battle Creek, Mich. O S

[73] Assignee: Clark Equipment Company, Battle [57] ABSTRACT Creek, Mich.

A front and lateral loading mechanism, primarily for Filed: 1970 lift trucks, in which a load supporting structure is [211 App] NO 77 846 mounted on the forward end of a boom and the boom is connected to a carriage by a pantograph mechanism capable of operating in an overcenter relationship to [52] US. Cl. 214/730 extend laterally to either side. One of the two links of [51] Int Cl B66f 9/14 the pantograph mechanism is continuous and the other [58] Field of Search 2l4/670, 730 link has upper and lower arms rigidly connected to one another by a shaft journalled in the continuous link, [56] Ref n s C t d with the arms on the opposite sides thereof. One link UNITED-STATES PATENTS is pivotally connected to the carriage and slidably con- 2 709 017 5 1955 Ulinski 214/730 acted the boQm, and the is slidably 39321894 3/1963 Gibson u 214/730 nected to the carriage and pivotally connected to the 3,360,078 12/1967 Hopfeld 187/9 boom. The carriage is normally mounted on an upright 3,390,798 7/1968 Dixon 214/730 of a lift truck for raising and lowering a load, and the 3,567,055 3/1971 Preto 214/730 load supporting structure, which may be a fork section, FOREIGN PATENTS OR APPLCATIONS is capable Of slewing from one side to the other as the 987 637 3H9 Great Britain 214/730 pantograph mechanism moves the boom laterally.

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INVENTORS HOWARD C. HANSEN JOHN S. MESSNER ATTORNEYS PMENIEW 2 SHEET 7% T INVENTORS HOWARD C. HANSEN BY JOHN S. MESSNER ATTORN EYS FRONT AND LATERAL LOADING MECHANISM A common practice of storing materials andproducts in warehouses, manufacturing plants, and shipping terminals is to use large storage rack structures spaced from one another by aisles for transporting, depositing and retrieving loads of material or products in the rack structures on either side of the aisle. The loading and unloading of the racks involve the operations of moving the loads longitudinally in either direction along the aisle and moving the loads laterally into and from the racks on either side of the aisle. Sideloading devices require a reach mechanism capable of moving the load from a central carrying position to a laterally extended position beyond the side of the vehicle. The minimum travel distance or stroke requirement of the mechanism is equal to the lateral dimension of the pallet and/or load, plus an additional several inches of aisle clearance within the aisle between the traveling truck and the storage rack structure. Most mechanisms used in transporting loads do not lend themselves conveniently.

to these requirements. For instance, if a conventional pantograph mechanism is used for such long strokes, its collapsed height is so great as to severely limit the ability of the device to place loads in a top storage rack shelf near the ceiling. If a single stage telescoping arrangement is used for the large stroke required, the collapsed dimension of the telescope is much greater than the width of the truck, and a two-stage telescoping arrangement becomes excessively complex and costly. One known device employs a combination of two basic mechanisms, consisting of a single-stage telescope device and a pantograph mechanism, the ,first device achieving aportion of the stroke requirement and the pantograph mechanism extending to achieve the balance of the stroke. Such arrangements have been inherently unsatisfactory and/or expensive. 7

Further, in order to perform the two longitudinal and lateral operations with lift trucks, the aisles between the rack structures have been relatively wide to permit some lateral maneuvering of the trucks when a load is being deposited in or removed from the racks, thus limiting the amount of storage space available for any given area. The prior lift trucks also have usually not had the ability to handle loads or more than one side or to transfera load from one side to the other in addition to picking up and depositing a load straight ahead and directly on the floor, and have often been of limited capacity and required precise positioningofthe truck and the use of special rack structures rather than conventional shelftype storage racks. a It is,"therefore, one. of the principal objects of the present. invention to provide a side loading attachment for fork lift trucks, which will enable the truck to handle full size pallet loadsin relatively narrow aisles and perform the operations of loading and unloading die rectly ahead and on either side of the truck, and which will pick up and deposit loads and transfer them from one side to the other near floor level or in any elevated position. y y

Another object of the invention is to provide a fork lift truck attachment which can be mounted on a conventional lift truck with little or no substantial change in the structure or operating mechanism of the truck, and which is relatively simple in construction and design and capable of effectively utilizing standard, shelftype rack structures.

Still another object of the invention is to provide a lift truck which is capable of handling loads to either side and in from without any lateral supporting means apart from the truck itself, and which will pick up a pallet load squarely and accurately without precise positioning of the truck, and will move the load into and from the rack on a straight line at right angles to the longitudinal center line of the truck.

A further object is to provide a lift truck or the like with a machanism which will skew pallet loads to either side of the truck and move the loads laterally to and from storage spaces, and which will retract laterally sufficiently to permit the truck to be moved in narrow aisles while the loads are held in their skewed positions, and also to skew the loads while the truck is in the aisle.

Additional objects and advantages of the invention will become apparent from the following description and accompanying drawings,-wherein:

FIG. 1 is a side elevational view of a lift truck having the present attachment or carriage assembly mounted thereon;

FIG. 2 is a top plan view of the lift truck shown in FIG. 1, including the present attachment;

FIG. 3 is a fragmentary top plan view of the present attachment, showing the attachment in two different positions in an aisle between two shelf racks;

FIG. 4 is a front elevational view of the truck and attachment shown in the preceding figures;

FIG. 5 is an enlarged side elevational view of the present attachment with the truck upright and front wheel shown in broken lines.

FIG. 6 is an enlarged front elevational view of the present attachment, showing it in two operating positions; and

FIG. 7 and 8 are enlarged fragmentary elevational views of operating mechanisms in the present attachment.

Referring more specifically to the drawings, and to I FIG. 1 in particular, numeral 10 designates generally a lift truck having a body 12, front and rear wheels 14 and 16, steering wheel 18, seat 20, and an upright 22 on the front of the truck having mounted thereon a carriage 24, and the present attachment indicated generally by numeral 26. The lift truck shown in the drawings on which the present attachment is used is considered conventional, for the purpose of the present description, and may be of any one of a number of well known types, including those powered by a battery driven electric motor or by a gasoline engine. Hence, the details of the lift truck will not be described in detail herein. a i f y The upright 22 and the carriage 24 mounted on the front of the truck likewise may be considered conventional for the purpose of the present description, the

one shown briefly consisting of an outer mast section 30 and inner mast section 32, telescopically arranged with respect to each other, and a hydraulic cylinder 34 for operating the inner mast section and the carriage mounted on the front of the uprighLThe inner and outer sections are each constructed of laterally spaced channel members or rails, and the upright shown in the drawings embodies a two stage lift system, although the present attachment can be used with other types of systems. The carriage 24 is mounted for vertical travel with respect to the rails of the inner sectionand the upright and carriage are hydraulically driven by fluid transmitted to and from the hydraulic actuating mechanisms on the upright and attachment by a plurality of hydraulic hoses (not shown) connected to the hydraulic system of the truck. The operating mechanisms of the upright and of the attachment are controlled from the operators compartment by control valves in the hydraulic system.

The side loading attachment 26 includes a pantograph mechanism, indicated generally by numeral 40, consisting of links 42 and 44, link 42 having a lower arm 46, pivotally connected to the carriage by a shaft 48, and an upper arm 49 slidably connected to the rear end of a forwardly extending boom 50, and link 44 having a lower arm 52 pivotally connected to the rear end of the boom and an upper arm 53 slidably connected to a frame 54 having a track 56 therein to which the arm is connected by a shaft 58. Arms 52 and 53 of link 44 are connected rigidly to one another by a rotatable shaft 60, journalled in link 42 at the center thereof, the arms being secured to the opposite ends of the shaft, forming a rigid structure with the shaft so that the two arms move in unison along with the rotation of shaft 60. The links of the pantograph mechanism move outwardly from a vertical position at the center where the two links 42 and 44 are substantially parallel to each other to one of the two laterally extended positions such as illustrated in FIG. 4. The lower end of arm 46 of link 42 is pivotally connected to carriage member 62 by horizontally disposed shaft 48, and the upper end of arm 52 of link 44 is pivotally connected to the lower part of boom 50 by a horizontally disposed shaft 74, and the upper end of arm 53 is connected to track 56 by shaft 58. With the lower ends of links 42 and 44 pivoted on fixed shafts 48 and 74, respectively, and with the upper ends of the two links slidably connected to vertical tracks 56 and 78, respectively, the boom maintains a vertical position as the pantograph mechanism moves outwardly from its centrally located position to its extended position, such as illustrated in FIG. 4.

One of the principal features of the present pantograph mechanism is the offset relationship of arms 52 and 53 of link 44 on shaft 60 on opposite sides of link 42. This permits the link to pass through the vertical center position from right to left and to extend laterally from the center to the same extent on either side of the center line, while maintaining the boom in its vertical position throughout the entire movement. Operation of the pantograph mechanism 40 is accomplished by a hydraulic cylinder 80, the lower end of which is pivotally connected to the carriage by pin 82, and the upper end of which is connected through piston rod 84 to arm 49 of link 42, in spaced relation to shaft 60. As the hydrau lic cylinder is extended, the pantograph mechanism is extended to the operators left, and as the hydraulic cylinder is contracted, the pantograph mechanism is first retracted to the center and then extended to the operator's right, the movement being to the same extent in both directions. The hydraulic cylinder is operated from the truck hydraulic system through flexible hydraulic lines (not shown) by controls located in the operator's compartment.

Frame 54, sliding on the inner most section, is movable with carriage 24 from the position shown in FIG. 4 to the top of the upright as the carriage and the attachment 26 are placed in the various vertical positions required for depositing and picking up loads. With the type of pantograph mechanism embodied in the present attachment, the load can be fully extended to the left hand lateral position illustrated in FIG. 4, fully retracted to the center position, and then extended laterally with the boom positionerd on the right hand side and the load positioned directly in line with the truck. The same operation can be performed with the load on the right hadn side of the truck. The load carrying boom 50 may be of various types of construction, the one illustrated being a fabricated type consisting of spaced panels welded to an inner framework to form a strong, rigid structure for carrying the load in the various extended positions illustrated in FIGS. 2 and 3. Throughout the operation of the present attachment, the boom remains in a forwardly extended position and moves to any position between the far right and left positions illustrated in FIG. 3.

The fork section generally indicated by the numeral 90, includes two spaced tines 92 and 94 adjustibly connected to upper and lower fork bars 96 and which in turn are rigidly connected to a post 100 journalled in a bearing 102 in the forward end of boom 50. This construction permits the fork mechanism to slew 180 between the right and the left positions illustrated in FIG. 3. A mechanism is preferably included for lowering the tines to and lifting them from the floor without movement of carriage 24. FIG. 8 shows a suitable mechanism for tilting and manipulating'the tines by tilting them from a substantially horizontal position on the floor to a slightly rearwardly tilted position for carrying and stabilizing the load, the mechanism including a section pivoted on a horizontally disposed pivot means 112 connected to post 100. A hydraulic cylinder 114 mounted on and secured to the post by bracket 116 pivots the tines upwardly as the piston in the cylinder is actuated by hydraulic fluid delivered through lines 118 and 120.

The fork section is operated to slew the tines from the forward position to either side, by the hydraulic means 120 shown in FIG. 7, consisting 'of a pair of hydraulic cylinders 122 connected to shaft 124 by a chain 126 reeved 180 degrees around a sprocket 127 rigidly secured to the upper end of shaft 124, the shaft being journalled in bearing 102 and connected rigidly to post 100. The ends of the chain are connected to the piston rods 128 of the two parallel cylinders by pins 129 or any other suitable securing means, and the two cylinders (only one of which can be seen) move the sections of the chain on opposite sides of the sprocket in either direction as the hydraulic fluid is admitted to and withdrawn from the ends of the two cylinders. Rotation of shaft 124 and post 100 to various angular positions within the 180 range, slews the forks to any desired position between the two lateral positions. Cylinders 122 are mounted in boom 50 behind post 100 and are connected to the hydraulic system of the truck by lines 130 and 132 and solenoid control valve 134, and are controlled by the operator by controls located in the operators compartment. Each cylinder is attached to cross member 136 of the boom by threaded studs 138 and opposed nuts 140 and 142 which can be adjusted on the stud to shift the respective cylinder lengthwise and thereby adjust chain 126 on the sprocket. The two cylinders 122 and chain 126 form a push-pull means for rotating sprocket 127 and post 100 as the pistons of the two cylinders move in opposite directions in response to the operation of the controls.

In the operation of the present front and lateral loading mechanism, starting with the carriage and attachment in their lowered position and the forks extending forwardly,'as seen in FIGS. 1 and 2, the truck moves forwardly, inserting forks 92 and 94 beneath a load. Cylinder 114 is then operated to tilt the forks upwardly to retain the load firmly on the fork as the load is carried by the truck. The hydraulic mechanism in the upright then raises the carriage and attachment to a suitable carrying distance above the floor, and the load is transported to the location where it is to be deposited, for example on storage racks on either side of an aisle. Assuming the load is to be deposited on one of the upper shelves of the rack, the carriage is elevated by the upright to the level of the selected shelf, and cylinders 122 are then operated to slew the fork section in the direction of the location where the load is to be deposited, and simultaneously the cylinder 80 of pantograph mechanism 40 is operated to withdraw boom 50 in the opposite direction, thereby placing the fork section and load in the position illustrated on the right hand side of FIG. 3. If the load is not now in proper position to insert it onto the shelf, the truck can readily be driven forwardly and rearwardly in the aisle and the carriage can easily be manipulated upwardly and downwardly to obtain the desired position. When the proper position has been achieved, cylinder 80 is then operated to advance the load laterally from the position indicated by the letter A of FIG. 3 to the position indicated by the letter B. As the pantograph mechanism operates, the load moves in a straight line laterally, thus permitting the operator to place the load precisely in the desired position. The load is then deposited on the shelf by lowering the carriage and tilting the tines of the fork section forwardly, and the fork is thereafter withdrawn from beneath the load by operating cylinder 80 to move the pantograph mechanism from its extended position to the right, as viewed in FIG. 3, to its extended position to its left, thus placing the fork section in position A, i.e., directly in line with the truck. While the tines are still in their lateral positions, the truck can easily be maneuvered without interference from the unloaded attachment. The same sequence of operation is performed in depositing loads on the opposite sides of the aisle, and the operation is merely reversed to remove a load from a shelf or other load supporting structure.

Carriage 24 is mounted for vertical movement on upright 22 by. a plurality of conventional carriage rollers with the upright lift cylinder furnishing the upward force for lifting the load; however, a torque force of substantial magnitude exists when fork section 90 is in one of its lateral positions, such as that illustrated in a FIG. 3. In order to obtain satisfactory performance of carriage 24 on upright 22, the torque force must be distributed or counteracted to prevent an excessive strain on the upright and to facilitate easy movement of the carriage on the upright. In the embodiment of the invention illustrated in the drawings, the torque forces are transmitted equally to both sides of the outer section of the upright by a system of squaring shafts and.

riage 24. The gears of each respective shaft travel on the two racks 156 and 157 as the carriage is moved upwardly and downwardly on the upright carrying a lateral load, thus distributing the torque uniformly between the two sides of the upright. The use of the squaring shaft system, in combination with the fork lift upright frame, serves to rotate the opposing forces so that the forces are aligned and parallel to the upright members which can then readily withstand additional in line forces, but which they might otherwise not be capable of supporting as torque resulting from a laterally offset load. While only three sets of shafts and gears are shown in the drawings, a greater of smaller number of shafts and gears may be used as required. This squaring mechanism is claimed in copending application, common assignee, U.S. Pat. Ser. No: 61,672, filed on Aug. 6, 1970.

As an alternative to the foregoing operational procedure, the lateral positioning of the load may be performed before the truck enters the aisle so that the only operations to be performed in the aisle are the elevation of the load and the lateral movement of inserting or withdrawing the load. Further, the truck, carriage and attachment can be operated in essentially the foregoing manner to shift the load from one extended side position without withdrawing the truck from the aisle.

The foregoing operation can be performed in an area only slightly larger than the width of the truck and attachment, and without the need of any lateral supporting structure or outriggers to stabilize the truck and/or attachment thereon. The squaring shaft system operates to distribute the load evenly on the upright so that no undue strain is placed on the upright.

While only one embodiment of the frontand side loader attachment has been described in detail herein, various changes and modifications may be made with out departing from the scope of the invention.

We claim:

a 1. A front and lateral loading mechanism for lift trucks, comprising a carriage for said trucks, a forwardly extending boom having an upper and lower portion, a load supporting section pivotally connected to the forward end of the boom for slewing to either side, a pantograph mechanism connecting the rear end of .said boom to said carriage, said mechanism having first and second links, shaft means connecting said links near the center thereof and being journalled in said first link, said second link having an arm rigidly connected to one end of said shaft means and extending generally upwardly and another arm rigidly connected to the other end of said shaft means and extending generally downwardly on the opposite side of said first link, one of said links being pivotally connected to said boom and slidably connected to said carriage and the other of said links being slidably connected to said boom and pivotally connected to said carriage, and a motor means for pivoting said links relative to one another on either side of the vertical center of said pantograph mechanism.

2. A front and lateral loading mechanism for lift trucks as defined in claim 1 in which said load supporting section includes two spaced, generally horizontally positioned forks.

3. A front and lateral loading mechanism for lift trucks as defined in claim 1 in which a vertically positioned post is connected to the forward end of said boom and supports said load supporting section.

4. A front and lateral loading mechanism for lift trucks as defined in claim 3 in which said post is rotatable and a motor means is mounted on said boom for rotating said post and thereby slewing said load supporting section.

5. A front and lateral loading mechanism for lift trucks as defined in claim 2 in which said post is rotatable and a motor means is mounted on said boom for rotating said post and thereby slewing said forks from the center to either side and from side to side.

6. A front and lateral loading mechanism for lift trucks as defined in claim 1 in which said carriage incl'udes a vertically positioned track and means connects said one link to said track.

7. A front and lateral loading mechanism for lift trucks as defined in claim 6 in which said means connects said upwardly extending arm of said second link to said vertically positioned track in slidable relation thereto.

8. A front and lateral loading mechanism for lift trucks as defined in claim 6 in which said boom has upper and lower portions at the rear end thereof, with one of said portions having a vertically positioned track therein, and a means for connecting one end of said links to said boom track in slidable relation thereto.

9. A front and lateral loading mechanism for lift trucks as defined in claim 8 in which said vertically positioned track in said boom is disposed in said upper portion.

10. A front and lateral loading mechanism for lift trucks as defined in claim 1 in which said motor means consists of a hydraulic cylinder means connected at one end to said carriage and at the other end to one of said links.

11. A front and lateral loading mechanism for lift trucks as defined in claim 1 in which said carriage is mounted on an upright for vertical travel to raise and lower a load on said load supporting section.

12. In a front and lateral loading mechanism having a carriage, and a load supporting structure: a pantograph mechanism connecting said structure to said carriage for lateral movement of said structure in both directions from the center of said mechanism, said mechanism having first and second links, shaft means connecting said links near the center thereof and being journalled in said first link, said second link having an ann rigidly-connected to one end of said shaft means and extending generally upwardly and another arm rigidly connected to the other end of said shaft means and extending generally downwardly on the opposite side of said first link, one of said links being pivotally connected to said structure and slidably connected to said carriage and the other of said links being slidably connected to said structure and pivotally connected to said carriage, and a motor means for pivoting said links relative to one another on either side of the vertical center of said mechanism.

13. A front and lateral loading mechanism as defined in claim 12 in which said carriage includes a vertically positioned track and means connects said one link to said track.

14. A front and lateral loading mechanism as defined in claim 13 in which said means connects said upwardly extending arm of said second link to said vertically positioned track in slidable relation thereto.

15. A front and lateral loading mechanism for lift trucks as defined in claim 13 in which said structure has upper and lower portions at the rear end thereof, with one of said portions having a vertically positioned track therein, and a means for connecting one end of one of said links to said track in slidable relation thereto.

16. A front and lateral loading mechanism for lift trucks as defined in claim 15 in which said vertically positioned track in said structure is disposed in said upper portion.

17. A front and lateral loading mechanism for lift trucks as defined in claim 12 in which said motor means consists of a hydraulic cylinder means connected at one end to said carriage and at the other end to one of said links.

18. A front and lateral loading mechanism as defined in claim 12 in which said load supporting structure is connected to said pantograph mechanism at right angles to the operating plane thereof.

19. A front and lateral loading mechanism for lift trucks as defined in claim 17 in which said hydraulic cylinder is connected to said other link and to said carriage in spaced lateral relationship to the pivotal connection of said other link to said carriage.

20. A front and lateral loading mechanism comprising a carriage, a load supporting structure and a pantograph mechanism supporting said structure on said carriage for lateral movement of said structure in both directions from the center of said mechanism, including two links pivotally connected to one another at their centers and extensible laterally in opposite directions, one of said links being pivotally connected to said structure and slidably connected to said carriage near the center thereof, and the other of said links being slidably connected to said structure and pivotally connected to said carriage near the center thereof, and a motor means for pivoting said links relative to one another on either side of the vertical center of said mechanism.

21. A front and lateral loading mechanism for lift trucks as defined in claim 20 in which said motor means consists of a hydraulic cylinder means connected at one end to said carriage and at the other end to one of said links.

22. A front and lateral loading mechanism for lift trucks as defined in claim 21 in which said hydraulic cylinder is connected to said other link and to said carriage in spaced lateral relationship to the pivotal connection of said other link to said carriage.

23. A front and lateral loading mechanism for use with a lift truck having an upright for handling loads in front and to either side, comprising a .carriage, a pantograph mechanism having two links pivotally connected to one another near the center thereof and being connected to said carriage and extensible and retractable on either side of said center, a load supporting structure connected to and disposed primarily on one side of the operating plane of said pantograph mechanism, and a motor means for operating said pantograph mechanism to and from its extended side positions on either side of said center.

24. A front and lateral loading mechanism as defined in claim 23 in which said motor means consists of a hydraulic cylinder means connected to said pantograph mechanism and to said carriage in spaced lateral relation to said center.

25. A front and lateral loading mechanism as defined in claim 23 in which a load distributing system is interposed between said carriage and said upright for minimizing the load unbalancing effect when a load is supported by said load support on either side of the center of said pantograph mechanism.

26. A front and lateral loading mechanism as defined in claim 25 in which said load distributing system includes a pair of laterally spaced racks mounted on said upright and a shaft and pinions interconnecting said racks.

27. A front and lateral loading mechanism as defined in claim 25 in which said load distributing system includes a pair of laterally vertically positioned racks mounted on said upright, a horizontally positioned shaft between said racks journalled on said carriage, and pinions on the end of said shaft meshing with said racks.

28. A front and lateral loading mechanism as defined in claim 27 in which a plurality of shafts and pinions interconnect said racks.

29. A front and lateral loading mechanism as defined in claim 23 in which said load supporting section includes a fork means for engaging the load and for moving the load between the front and two side positions.

30. A front and lateral loading mechanism as defined in claim 29 in which said fork means includes a vertically positioned post and two spaced generally horizontally positionedforks supported on said post.

31. A front and lateral loading mechanism as defined in claim 30 in which said fork means is pivotally mounted on a horizontal axis on said load supporting section for movement between a downwardly tilted, floor contacting position and an upwardly tilted, load transporting position, and a motor means for tilting said fork means between said two positions.

32. A front and lateral loading mechanism as defined in claim 31 in which said motor means consists of a hydraulic cylinder.

33. A front and lateral loading mechanism as defined in claim 23 in which a boom is mounted on and extends forwardly from said pantograph mechanism, a fork means is pivotally attached on a vertical axis to the forward end of said boom, and a power operating means interconnects said boom and fork means for slewing said fork means from side to side.

34. A front and lateral loading mechanism as defined in claim 33 in which said power operating means includes a sprocket connected to said fork means, a pair of hydraulic cylinder means mounted on said boom, and a chain reeved on said sprocket and connected at opposite ends to said pair of hydraulic cylinder means.

UNITED STATESiPATENT OFFICE I CERTIFICATE OF vCORRECTIOTIT Patent No. 5,7 2, 588 Dated October 2, 1973 glnventofls) Howard C. Hansen et y al.

It is certified that error" appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

column 2, line 55, change FIG. to FIGS. column 5, line'6l, change "most" to mast column r, line 5, change "positionerd" to positioned line 17, change "adjustibly" to adjustably line, l8, change "'90" to 98 line- 55, 7 Change "120" to ha-- 119 a column 6,' line 10, delete "they" v line 11, change "as to the line 15, change "of" to or Signed and sealed this 8th day of October 197 +o ?(SEAL) Attest:

MCCOY M. GIBSON JR. c c. MARSHALL DANN Attesting Officer r Commissioner of Patents M w (10459) r v V USiCOMM-DC scan-poo I u.s. GOVERNMENT PRINYING orncs: 930 

1. A front and lateral loading mechanism for lift trucks, comprising a carriage for said trucks, a forwardly extending boom having an upper and lower portion, a load supporting section pivotally connected to the forward end of the boom for slewing to either side, a pantograph mechanism connecting the rear end of said boom to said carriage, said mechanism having first and second links, shaft means connecting said links near the center thereof and being journalled in said first link, said second link having an arm rigidly connected to one end of said shaft means and extending generally upwardly and another arm rigidly connected to the other end of said shaft means and extending generally downwardly on the opposite side of said first link, one of said links being pivotally connected to said boom and slidably connected to said carriage and the other of said links being slidably connected to said boom and pivotally connected to said carriage, and a motor means for pivoting said links relative to one another on either side of the vertical center of said pantograph mechanism.
 2. A front and lateral loading mechanism for lift trucks as defined in claim 1 in which said load supporting section includes two spaced, generally horizontally positioned forks.
 3. A front and lateral loading mechanism for lift trucks as defined in claim 1 in which a vertically positioned post is connected to the forward end of said boom and supports said load supporting section.
 4. A front and lateral loading mechanism for lift trucks as defined in claim 3 in which said post is rotatable and a motor means is mounted on said boom for rotating said post and thereby slewing said load supporting section.
 5. A front and lateral loading mechanism for lift trucks as defined in claim 2 in which said post is rotatable and a motor means is mounted on said boom for rotating said post and thereby slewing said forks from the center to either side and from side to side.
 6. A front and lateral loading mechanism for lift trucks as defined in claim 1 in which said carriage includes a vertically positioned track and means connects said one link to said track.
 7. A front and lateral loading mechanism for lift trucks as defined in claim 6 in which said means connects said upwardly extending arm of said second link to said vertically positioned track in slidable relation thereto.
 8. A front and lateral loading mechanism for lift trucks as defined in claim 6 in which said boom has upper and lower portions at the rear end thereof, with one of said portions having a vertically positioned track therein, and a means for connecting one end of said links to said boom track in slidable relation thereto.
 9. A front and lateral loading mechanism for lift trucks as defined in claim 8 in which said vertically positioned track in said boom is disposed in said upper portiOn.
 10. A front and lateral loading mechanism for lift trucks as defined in claim 1 in which said motor means consists of a hydraulic cylinder means connected at one end to said carriage and at the other end to one of said links.
 11. A front and lateral loading mechanism for lift trucks as defined in claim 1 in which said carriage is mounted on an upright for vertical travel to raise and lower a load on said load supporting section.
 12. In a front and lateral loading mechanism having a carriage, and a load supporting structure: a pantograph mechanism connecting said structure to said carriage for lateral movement of said structure in both directions from the center of said mechanism, said mechanism having first and second links, shaft means connecting said links near the center thereof and being journalled in said first link, said second link having an arm rigidly connected to one end of said shaft means and extending generally upwardly and another arm rigidly connected to the other end of said shaft means and extending generally downwardly on the opposite side of said first link, one of said links being pivotally connected to said structure and slidably connected to said carriage and the other of said links being slidably connected to said structure and pivotally connected to said carriage, and a motor means for pivoting said links relative to one another on either side of the vertical center of said mechanism.
 13. A front and lateral loading mechanism as defined in claim 12 in which said carriage includes a vertically positioned track and means connects said one link to said track.
 14. A front and lateral loading mechanism as defined in claim 13 in which said means connects said upwardly extending arm of said second link to said vertically positioned track in slidable relation thereto.
 15. A front and lateral loading mechanism for lift trucks as defined in claim 13 in which said structure has upper and lower portions at the rear end thereof, with one of said portions having a vertically positioned track therein, and a means for connecting one end of one of said links to said track in slidable relation thereto.
 16. A front and lateral loading mechanism for lift trucks as defined in claim 15 in which said vertically positioned track in said structure is disposed in said upper portion.
 17. A front and lateral loading mechanism for lift trucks as defined in claim 12 in which said motor means ocnsists of a hydraulic cylinder means connected at one end to said carriage and at the other end to one of said links.
 18. A front and lateral loading mechanism as defined in claim 12 in which said load supporting structure is connected to said pantograph mechanism at right angles to the operating plane thereof.
 19. A front and lateral loading mechanism for lift trucks as defined in claim 17 in which said hydraulic cylinder is connected to said other link and to said carriage in spaced lateral relationship to the pivotal connection of said other link to said carriage.
 20. A front and lateral loading mechanism comprising a carriage, a load supporting structure and a pantograph mechanism supporting said structure on said carriage for lateral movement of said structure in both directions from the center of said mechanism, including two links pivotally connected to one another at their centers and extensible laterally in opposite directions, one of said links being pivotally connected to said structure and slidably connected to said carriage near the center thereof, and the other of said links being slidably connected to said structure and pivotally connected to said carriage near the center thereof, and a motor means for pivoting said links relative to one another on either side of the vertical center of said mechanism.
 21. A front and lateral loading mechanism for lift trucks as defined in claim 20 in which said motor means consists of a hydraulic cylinder means connected at one end to said carriage and at the other end to one of said links.
 22. A fronT and lateral loading mechanism for lift trucks as defined in claim 21 in which said hydraulic cylinder is connected to said other link and to said carriage in spaced lateral relationship to the pivotal connection of said other link to said carriage.
 23. A front and lateral loading mechanism for use with a lift truck having an upright for handling loads in front and to either side, comprising a carriage, a pantograph mechanism having two links pivotally connected to one another near the center thereof and being connected to said carriage and extensible and retractable on either side of said center, a load supporting structure connected to and disposed primarily on one side of the operating plane of said pantograph mechanism, and a motor means for operating said pantograph mechanism to and from its extended side positions on either side of said center.
 24. A front and lateral loading mechanism as defined in claim 23 in which said motor means consists of a hydraulic cylinder means connected to said pantograph mechanism and to said carriage in spaced lateral relation to said center.
 25. A front and lateral loading mechanism as defined in claim 23 in which a load distributing system is interposed between said carriage and said upright for minimizing the load unbalancing effect when a load is supported by said load support on either side of the center of said pantograph mechanism.
 26. A front and lateral loading mechanism as defined in claim 25 in which said load distributing system includes a pair of laterally spaced racks mounted on said upright and a shaft and pinions interconnecting said racks.
 27. A front and lateral loading mechanism as defined in claim 25 in which said load distributing system includes a pair of laterally vertically positioned racks mounted on said upright, a horizontally positioned shaft between said racks journalled on said carriage, and pinions on the end of said shaft meshing with said racks.
 28. A front and lateral loading mechanism as defined in claim 27 in which a plurality of shafts and pinions interconnect said racks.
 29. A front and lateral loading mechanism as defined in claim 23 in which said load supporting section includes a fork means for engaging the load and for moving the load between the front and two side positions.
 30. A front and lateral loading mechanism as defined in claim 29 in which said fork means includes a vertically positioned post and two spaced generally horizontally positioned forks supported on said post.
 31. A front and lateral loading mechanism as defined in claim 30 in which said fork means is pivotally mounted on a horizontal axis on said load supporting section for movement between a downwardly tilted, floor contacting position and an upwardly tilted, load transporting position, and a motor means for tilting said fork means between said two positions.
 32. A front and lateral loading mechanism as defined in claim 31 in which said motor means consists of a hydraulic cylinder.
 33. A front and lateral loading mechanism as defined in claim 23 in which a boom is mounted on and extends forwardly from said pantograph mechanism, a fork means is pivotally attached on a vertical axis to the forward end of said boom, and a power operating means interconnects said boom and fork means for slewing said fork means from side to side.
 34. A front and lateral loading mechanism as defined in claim 33 in which said power operating means includes a sprocket connected to said fork means, a pair of hydraulic cylinder means mounted on said boom, and a chain reeved on said sprocket and connected at opposite ends to said pair of hydraulic cylinder means. 